NHER 49748 (Monument record) - Multi-period remains including evidence for Late Saxon to medieval charcoal production and iron smelting

2004-2005. Desk-based Assessment.
Assessment of proposed line of Norwich Northern Distributor Road.
See reports (S1) and (S2) for further details.
P. Watkins (HES), 28 July 2015.

November 2009. Trial Trenching.
Evaluation of site on proposed line of Norwich Northern Distributor Road (Site C1).
Fourteen of the twenty trenches excavated in this field revealed archaeologically significant features. These features included ditches and a number of pits. Generally the pits were fairly unremarkable, the exceptions being one that had a charcoal-rich primary fill and another that was of considerable size (being at least 3.1m wide and over 1m deep).
Dating evidence was scarce. One feature that was either a ditch or a large pit produced a single small Early Neolithic pottery sherd and a small assemblage of worked flints that included a blade of possible Early Neolithic date. Finds recovered from other features were largely restricted to small quantities of later prehistoric flint. The one exception was a single sherd of post-medieval/modern pottery recovered from a ditch fill.
Although several trenches were placed to investigate a number of previously identified linear cropmarks (NHER 50993) there were no sub-surface deposits that could be convincingly associated with these features. A number of similarly aligned plough marks were however noted and it was suggested that these may have been the linear features visible as cropmarks.
See report (S3) for further details. The results of this work are also summarised in (S4).
Amended by P. Watkins (HES), 30 July 2015.

May 2014-January 2015. Geophysical Survey.
Magnetometer survey on proposed line of the Norwich Northern Distributor Road (Area C1).
The responses of greatest archaeological significance were a group of linear anomalies in the eastern part of the site that appeared to present three sides of a square or rectilinear enclosure, at least part of which clearly lay beyound the northern edge of the field. Numerous discrete anomalies were recorded within and in the immediate vicinity of this enclosure, at least some of which may represent pits, post-holes and spreads of magnetically enhanced material.
Although numberous other discrete areas of magnetic enhancement were recorded across the remainder of the site these are mostly regarded as geological in origin.
The only other responses of note were two north-east to south-west aligned linear anomalies that clearly correspond with former field boundaries shown on the Ordnance Survey Six-inch First Edition map (S5). Various other linear anomalies are all thought to have been the result of agricultural activity.
The was again no evidence for surviving subsurface remains associated with fragmentary cropmarks recorded in the central part of this site (NHER 50993).
See report (S6) for further details.
P. Watkins (HES), 23 February 2021.

April-September 2015. Trial Trenching.
Evaluation of site on proposed line of Norwich Northern Distributor Road (Field C1).
This phase of work saw the excavation of an additional 30 trenches in order to investigate areas to the south and north of the strip examined in 2009. Several of the trenches were positioned to target the enclosure identified by the preceding geophysical survey, which was found to be of probable medieval date.
There was little evidence for pre-medieval activity on the site. A single feature of uncertain nature within the enclosure was potentially prehistoric, producing three sherds of Early Neolithic pottery, a potentially contemporary worked flint and a single fragment of burnt flint. Otherwise, evidence for earlier phases of activity was limited to a small number of Mesolithic/Early Neolithic and Neolithic/Bronze Age worked flints and several Roman pottery sherds - all of which were probably residual within later features.
All four of the trenches placed across the enclosure revealed corresponding ditches. These were of varying size, which, coupled with the intermittent nature of the geophysical anomalies suggests this enclosure was not necessarily bounded by a single continuous ditch of consistent form. All four trenches also revealed a similarly-aligned ditch relatively close to the outer side of the main enclosure ditch. These potentially represented an outer circuit of ditch that had not been detected by the geophysical survey. Although no finds were recovered from the excavated sections of the main enclosure ditch, reasonably significant quantities of medieval pottery were recovered from two linear features within its interior. Other finds recovered from features within the enclosure included fragments of iron working debris (including tap slag from iron smelting) and fragments of lava quern. Medieval pottery sherds and iron slag were also recovered from one of the outer ditches.
The 85 medieval pottery sherds recovered from features within and near the enclosure are almost entirely of high medieval date, apart from three early medieval sherds and a single sherd of LMT (late medieval and transitional) pottery.
The trenches excavated across the remainder of the site revealed only scattered remains of limited interest. Two isolated undated pits with charcoal-rich fills were similar to a feature revealed during the 2009 trenching and had potentially been associated with charcoal production.
Other features included several ditches that were either perpendicular or parallel to the modern field boundaries, one of which produced two sherds of post-medieval/modern pottery. Other evidence for post-medieval activity was limited to a pit at the southern edge of the site that produced a single fragment of a glass vessel and a single pantile recovered from a feature of uncertain nature within the enclosure.
See report (S7) for further details.
P. Watkins (HES), 23 February 2021.

January-September 2016. Strip Map and Sample Excavation.
Excavations on route of Norwich Northern Distributor Road.
Two parts of this site were subject to further excavation; a small area at the western end of the site (Area 9 East) and a much longer block at its eastern end (Area 10).
The smaller area excavated at the western end of the site (Area 9 East) revealed two loose clusters of pits, a group of probable tree throw hollows and a short length of ditch.
The small number of finds recovered suggested that the majority of these features were probably prehistoric, a single undatable fragment of ceramic building material being the only later object found. At least two distinct phases of prehistoric activity were represented, with an Early Neolithic pottery sherd and a blade core of Mesolithic/Early Neolithic date recovered from the group of tree throws, and two of the pits found to contain Late Neolithic/Early Bronze Age Beaker pottery. Samples taken from the fills of the pits containing Beaker pottery both produced hazelnut shells. One of these features also contained a number of flint flakes that were potentially contemporary with the pottery. The short length of ditch produced several worked flints of probable Neolithic/Bronze Age date and was therefore also regarded as a potentially prehistoric in date.
The excavation at the eastern end of the site (Area 10) revealed the south side of the enclosure identified by the earlier phases of work but none of its interior (which was deliberately preserved in situ). Remains exposed across the remainder of the excavated area included several ditches and numerous discrete features. A significant proportion of the latter were though probable tree throw hollows and other natural features. The groups of more convincing pits appear to have represented multiple phases of activity, although the majority produced little in the way of dating evidence. Those most likely to be prehistoric were a diffuse group at the western end of the excavated area that produced several sherds of Late Neolithic/Early Bronze Age pottery. Although a small assemblage of Mesolithic/Early Neolithic, Late Neolithic and Neolithic/Bronze Age worked flints was also recovered these were mostly either unstratified or residual in later features.
The various other groups of discrete features were probably associated with later phases of activity. Some of the larger features were interpreted as extraction pits while others were possibly associated with industrial activity. The latter included several features interpreted as probable iron smelting furnaces and a number of pits with charcoal-rich fills thought to have been associated with charcoal production. As least some of these remains were of probable Saxon date with Early Saxon pottery recovered from one and Late Saxon sherds found in several others. A Middle/Late Saxon radiocarbon date of cal AD 689-881 at 95% probability (SUERC-71675; 1231 +/- 29 BP) was also obtained for material from one of the charcoal pits. These features were though clearly associated with multiple phases of activity as another produced as large assemblage of medieval pottery.
The pits interpreted as possible iron smelting furnaces were clustered in the central part of the excavation area and contained large quantities of tap slag and fired clay likely to represent fragments of furnace linings and superstructure. Unfortunately, none produced any dating evidence.
Other significant features beyond the enclosure included a group of 11 post-holes that potentially represented some form of structure. These also produced no finds.
The exposed section of the enclosure was comprised of three intercutting ditches of varying size. As had been suggested by the earlier trial trenching it was found to be surrounded by an outer, narrower ditch. These features produced pottery of predominantly high medieval date, ceramic building material, animal bone and a significant amount of tap slag and other metal-working debris. The presence of this metal-working debris suggests that iron smelting had most probably been taking on place on the site during the medieval period, although an earlier start or later end to this activity cannot be ruled out. Further slag was also recovered from a large probable extraction pit located close to the enclosure.
Only a small amount of late medieval pottery was recovered and there was only limited evidence for subsequent activity on the site. Two adjacent north-east to south-west aligned ditches clearly coincide with one of the field boundaries depicted on the Ordnance Survey First Edition Six-inch map (S5) and a pair of similarly aligned ditches to the west are also most probable post-medieval in date. Other relatively recent features included a large cluster of probable extraction pits.
Information from draft assessment report. Final version awaited.
P. Watkins (HES), 5 April 2021.